Papers by Keyword: Elliptical Mirror

Abstract: Numerically controlled local wet etching (NC-LWE) is a novel technique to fabricate the ultraprecision optical components and/or finishing the functional materials. In this technique, a figuring is performed by controlling the dwelling time of the combination nozzle, which consists of a supply and a suction part of an etchant, on the workpiece. In this paper, we proposed fabrication process of millimeter-thick elliptical neutron focusing mirror substrate by applying NC-LWE figuring involving CeO2 slurry polishing. We fabricated a millimeter-thick elliptical neutron focusing mirror substrate with a figure error of less than 0.2 μm and obtained a surface roughness of less than 0.15 nm rms.

Abstract: Numerically controlled local wet etching is a novel figuring method for fabricating the ultraprecision optical components and/or finishing the functional materials. In this method, localized wet etching area is formed by applying the combination nozzle which consists of a supply part and a suction part of an etchant, and the removal volume at any point on the workpiece surface is determined by the dwelling time of the nozzle. In this paper, we proposed the two-step figuring process, which consists of a rough figuring process by applying a one-dimensional numerically controlled scanning using a large rectangular nozzle and a finishing process by applying two-dimensional numerically controlled scanning using a small circular nozzle, for figuring the plano-aspherical mirror. By applying the two-step figuring process, we fabricated the plano-elliptical neutron focusing mirror with the figure accuracy of less than 0.5 µm and succeeded in achieving the focusing gain of 6.